Expandable Roller

ABSTRACT

A hair roller includes a longitudinally extending hair curling portion defined between a pair of opposed end members. The hair curling portion is expandable and retractable in a radial direction with respect to the longitudinal axis of the hair curling portion, in response to relative movement of the end members with respect to each other.

FIELD OF THE INVENTION

The present invention relates to hair rollers and, more particularly, tohair rollers with a reconfigurable hair curling surface.

BACKGROUND OF THE INVENTION

A typical hair roller comprises a cylindrical roller body with a haircurling surface configured for curling hair by heated contact. In use, ahair roller is heated first and then tresses of hair are wrapped aroundthe roller body to form curls through heat conduction. In another typeof hair rollers, tresses of hair are first wrapped on a roller and heatis then applied to the hair to be curled through heating of the rollerbody by inserting a heated rod into an axial aperture of the hairroller.

Hair curling using conventional hair rollers is essentially byapplication of heat and tension to the hair being curled. The curlingtension applied to the hair is largely obtained by subjecting the hairbeing curled to conform tightly to the curvature of the roller body.Although a hair roller should ideally engage tresses of hair tightly formaximum curling efficiency, it is noted that tresses of hair always losesome degree of curling tension after the tresses of hair have been woundon a conventional hair roller. On the other hand, when tresses of hairare tightly engaged on a hair roller, it will be difficult to releasethe curled hair from the roller without adversely affecting theintegrity of the curls.

It is desirable if there can be provided a hair curler which mitigatesshortcomings of conventional hair rollers.

SUMMARY OF THE INVENTION

According to the present invention, there is provided a hair rollercomprising a longitudinally extending hair curling portion definedbetween a pair of opposed end members, wherein said hair curling portionis expandable and retractable in a radial direction with respect to thelongitudinal axis of said hair curling portion in response to relativemovement of said end members with respect to each other.

A hair roller having an expandable hair curling portion will provide auser an opportunity to tighten the engagement between the tresses ofhair to be styled and the hair curling surface whereby an increased haircurling tension can be applied and the tresses of hair will follow thecurvature of the hair roller more closely. On the other hand, theprovision of a retractable hair curling portion facilitates easierseparation between a hair roller and the hair after curling has beencompleted.

In an exemplary embodiment of this invention, the hair curling portionand the end members are arranged so that said hair curling portion isexpandable and retractable in response to rotary movement of said endmembers relative to each other. A rotary movement provides a mechanicaladvantageous arrangement so that a user can adjust the expansion andretraction of the hair portion with ease.

The hair curling portion may be arranged to expand and retract graduallyin response to movement of said end members relative to each other. Ahair roller with a gradual expansion and retraction facility will afforda user an opportunity to select an appropriate curl tension anddimension suitable for specific purposes.

As an example, the hair curling portion may assume a longitudinallyconvexly curved hair curling region located intermediate the end membersresponsive to said relative movement of the end members.

The convexly curved region may extend circumferentially around saidlongitudinal axis.

As a further example, the convexly curved region may have a bell-shapedlongitudinal profile along its length.

In a convenient example, the end members are interconnected by a rigidtube, and at least one of said end members is moveable relative to saidrigid tube such that the longitudinal separation between the end membersis variable responsive to rotary movement of said at least one of saidend members relative to said rigid tube.

So that a hair roller can obtain operational heat from an externalheated rod more efficiently, the rigid tube may be formed from athermally conductive material.

To facilitate relative movement between the end members, at least one ofsaid end members may be mounted on said rigid tube by threadedengagement.

In an exemplary embodiment, the radial expansion of the hair curlingportion is at a maximum mid-way between said end members, and whereinthe extent of radial expansion gradually diminishes from said maximumtowards said longitudinal ends. The non-linear longitudinal profile ofthe hair curling portion across the length of the hair curling portionprovides extra curvy effects while achieving the purpose of tightlysecuring tresses of hair on the hair roller. For example, the extent ofradial expansion of said hair curling portion may be at a minimumadjacent the longitudinal ends of said hair curling portion.

In an embodiment, the hair curling portion defines a hair curlingsurface which may be reconfigurable between a cylindrical surface havinga substantially uniform cross-section along its length and a bulgedsurface having an arcuate longitudinal profile. For example, the bulgedsurface may have a convexly curved longitudinal profile.

The hair curling portion may comprise a flexible or resilientlydeformable cage which comprises a plurality of longitudinally extendingflexible or resiliently deformable elongate members which collectivelydefine a hair curling surface.

The deformable cage may overlay the rigid tube and is moveable relativeto said rigid tube. In addition, the deformable cage may bulge at orabout the middle of its length when subjected to an axial compressiveforce acting at the axial ends of said cage. Furthermore, the deformablecage may be integrally formed from a resilient metallic sheet, foil orcylinder. For example, the resiliently deformable cage may be formed ofsteel, aluminium or like resilient materials.

As a useful example, the deformable cage may comprise a plurality oflongitudinally extending strips defining a plurality of longitudinallyextending channels located there-between, and wherein the totality ofsaid longitudinally extending strips forms a convexly curved bulgingsurface surrounding said rigid tube when subjected to an axialcompressive force applied at the axial ends of said cage.

Each end member may comprise a circular cap member and at least one ofsaid circular members is rotatable relative to said hair curling portionand about said longitudinal axis, and wherein the separation distancebetween said cap members is variable upon relative rotation between saidcircular member and said hair curling portion.

The hair styling portion may expand or retract radially in response torelative rotation between said circular member and said hair curlingportion.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention will be explained infurther detail below by way of example and with reference to theaccompanying drawings, in which:—

FIG. 1 is a perspective view of a hair roller illustrating a firstpreferred embodiment of this invention,

FIG. 2 is a side view of the hair roller of FIG. 1,

FIG. 3 is a top plan view of the hair roller of FIG. 1,

FIG. 4 shows an end view of the roller of FIG. 3 from one end,

FIG. 5 shows an end view of the roller of FIG. 3 from another end,

FIG. 6 is a longitudinal cross-sectional view of the roller of FIG. 1along the section line B-B of FIG. 3,

FIG. 7 is a perspective view of the roller of FIG. 1 in an expandedconfiguration,

FIG. 8 is a longitudinal cross-sectional view of the roller of FIG. 7,

FIG. 9 is an exploded view of the hair roller of FIGS. 1 to 8,

FIG. 10 is a perspective view depicting a hair roller of a secondembodiment of this invention,

FIG. 11 is a longitudinal cross-section of the hair roller of FIG. 10,

FIG. 12 is a side view of the hair roller of FIG. 10,

FIG. 13 is a perspective view depicting a third embodiment of the hairroller of this invention,

FIG. 14 is a longitudinal cross-sectional view of the hair roller ofFIG. 13, and

FIG. 15 is a longitudinal cross-sectional view depicting the hair rollerof FIG. 10 with the cage in its expanded form.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The hair roller 100 shown in FIGS. 1 to 9 comprises a hair curling body110, a pair of end members 130, 140 and a support shaft 120 formed of arigid tube which interconnects the end members.

The support shaft 120 comprises a rigid tube which is formed from metalor a metal alloy. An end member 130 is fixedly attached to one axial endof the support shaft 120 while the other end member 140 is moveablyattached to the other axial end of the support shaft 120 via screwthreads. The end members comprise circular caps which are coaxial withrespect to each other and/or with respect to the support shaft. Withsuch a coupling engagement, the end members are rotatable relative toeach other about the longitudinal axis, and when the end members sorotate, the axial or longitudinal distance of separation between the endmembers is variable. Due to the helical or screw threaded couplingbetween an end member 140 and the rigid tube, the axial separationbetween the end members is variable through relative rotary movement ofthe end members about the longitudinal axis of the hair curling body.More particularly, the end members can move axially towards and awayfrom each other to vary the effective length of the hair styling portionby rotating the screw cap 142 on the screw thread. In use, a user canrotate the screw cap 142 and therefore the end member 140 to advance orretreat the end member 140 towards or away from the other end member130.

Each of the end members comprises an insulating outer cover 132, 142.Each insulating cover is substantially circular, similar to an endmember of a conventional hair roller. The insulating cover is made, forexample, of plastics or other appropriate insulating materials. Aplurality of graduations is formed on the circumference of the circularend members to provide a friction contact interface for facilitateeasier rotation of the moveable end member 140 by a user.

The hair curling body 110 comprises a resiliently deformable cage whichis resiliently expandable when subject to an axial compressive forcewhich is applied at the longitudinal ends of the cage. The cagecomprises a pair of opposed end rings which are interconnected by aplurality of elongate strips and each of the rings is adjacent to acorresponding end member. The elongate strips are parallel and aredistributed around the circumference of the circular ring. An elongatechannel is defined intermediate a pair of adjacent elongate strips andthe plurality of elongate strips collectively define a plurality ofelongate channels which are distributed around the circumference of thecircular rings. More particularly, the elongate strips are evenlydistributed around the circumference of the circular rings. The cage isintegrally moulded or stamped from a single metallic sheet or foil toprovide adequate uniformity of resilience. In addition, the elongatestrips are covered by a thermal insulator, such as, for example, velvetor other fabrics, which also provides friction against relative movementbetween the hair curling portion and the hair under retention.

In its neutral and un-deformed form, the cage is substantiallycylindrical with its longitudinal axis coaxial with that of the supportshaft and having a substantially uniform circular cross section alongits length, as shown in FIGS. 1 to 6 and 9. To provide adequateresilience so that a deformed (or radially expanded) cage will return toits neutral (or retracted) form when the deformation tension has beenremoved, the cage is formed from a resilient material such as steel,copper, aluminium or other resilient metal or metal alloys.

The cylindrical metal cage is carried on the support shaft 120 with itslongitudinal ends in contact with or in proximity of the end members130, 140. To allow relative slide movements between the support shaftand the cage, the cross-section of the metal cage is slightly largerthan that of the support shaft. The metallic cage is adapted so thatwhen the pair of end members 130, 140 move towards each other, theresulting lateral compressive force will cause the metal cage to bulgenear its middle, as shown in FIGS. 7 and 8. When the lateral compressiveforce is removed, the resilience of the metallic cage will return to itsun-stressed cylindrical shape. The metallic cage is made, for example,of aluminium sheet with a plurality of longitudinally extending metallicstrips 112 separated by another plurality of longitudinal channels orelongate apertures 114 so that the metallic strips will be bent convexlyoutward when subject to a lateral compressive force acting on itslongitudinal ends. Of course, the metallic cage can be made of otherresilient metal such as steel. As an alternative, the metallic cage canbe designed so that a plurality of ripples are formed when subject to alateral compressive force.

An exemplary use of the hair roller of this invention will be describedbelow with reference to the Figures. Initially, tresses of hair arewrapped or wound on the hair curling body 110. When tresses of hair havebeen wrapped on the hair curling body, the pair of end members is movedtowards each other. When the pair of end clamping members aresufficiently moved towards each other, for example, by rotating thescrew-threaded end member 140 towards the fixed attached end member 130,the metallic cage is also caused to bulge at its middle portion so thatit has a substantially convex arcuate profile along its length and thisradial expansion will help to more tightly pack or squeeze the curlalong the radial direction to achieve the desirable effects.

In a second embodiment of the invention, construction of the roller 200is substantially identical to that of the first embodiment, although thecage 216 is integrally formed from rubber or resilient plastics, and theend members 230, 240 are also moulded from rubber, plastics or otherinsulating materials. Moreover, there are no axially extendingprotrusions formed on the inside of the end second members, and aplurality of axially extending graduations 238 for friction engagementof the end members by the fingers of a user is distributed on thecircumference of the end members.

Unless otherwise specified, features appearing in FIGS. 10-12 aredesignated with the same numerals of FIGS. 1-9 plus 100.

In another embodiment, the roller is identical to that of the firstembodiment, but the rigid tube is moulded from plastics.

In yet another embodiment, the roller is identical to that of the firstembodiment, but no longitudinal hair engaging protrusions extend fromthe end members.

In a third embodiment as shown in FIGS. 13-15, the roller 300 isidentical to that of the second embodiment, but some or all of theelongate strips are formed with small protrusions distributed along thelength of the strips for providing additional friction for hairretention.

Unless otherwise specified, features appearing in FIGS. 13-15 aredesignated with the same numerals of the second embodiment plus 100.

While the present invention has been explained by reference to theexamples or preferred embodiments described above, it will beappreciated that those are examples to assist understanding of thepresent invention and are not meant to be restrictive. Variations ormodifications which are obvious or trivial to persons skilled in theart, as well as improvements made thereon, should be considered asequivalents.

Furthermore, while the present invention has been explained by referenceto a hair curler with a metallic cage body, it should be appreciatedthat the invention can apply, whether with or without modification, tohair curlers with other forms of expandable hair curling surface withoutloss of generality.

1-21. (canceled)
 22. A hair roller comprising a longitudinally extendinghair curling portion defined between a pair of opposed end clampingmembers wherein, upon relative rotary movement of said end clampingmembers with respect to each other, said hair curling portion isexpandable and retractable in a radial direction and the axialseparation between said end clamping members is variable.
 23. A hairroller according to claim 22, wherein the effective length of said haircurling portion is variable upon relative rotation of said end clampingmembers.
 24. A hair roller according to claim 22, wherein axiallyextending hair engaging protrusions are formed on said end clampingmembers.
 25. A hair roller according to claim 22, wherein said haircurling portion assumes a longitudinally convexly curved hair curlingregion located intermediate the end clamping members responsive to saidrelative rotary movement of the end clamping members.
 26. A hair rolleraccording to claim 25, wherein said convexly curved region extendscircumferentially around said longitudinal axis.
 27. A hair rolleraccording to claim 22, wherein said end clamping members areinterconnected by a rigid tube, and wherein at least one of said endclamping members is moveable relative to said rigid tube such that thelongitudinal separation between the end clamping members is variableupon relative rotary movement between said at least one of said enddamping members and said rigid tube.
 28. A hair roller according toclaim 27, wherein said rigid tube is formed from a thermally conductivematerial.
 29. A hair roller according to claim 27, wherein said at leastone of said end clamping members is mounted on said rigid tube bythreaded engagement.
 30. A hair roller according to claim 22, whereinsaid hair curling portion defines a hair curling surface, and whereinsaid hair curling surface is reconfigurable between a cylindricalsurface having a substantially uniform cross-section along its lengthand a bulged surface having an arcuate longitudinal profile.
 31. A hairroller according to claim 22, wherein said hair curling portioncomprises a flexible or resiliently deformable cage, said cagecomprising a plurality of longitudinally extending flexible orresiliently deformable elongate members which collectively define a haircurling surface.
 32. A hair roller according to claim 31, wherein saidflexible or resiliently deformable cage overlays said rigid tube and ismoveable relative to said rigid tube.
 33. A hair roller according toclaim 31, wherein said deformable cage bulges at or about the middle ofits length when subjected to an axial compressive force acting at theaxial ends of said cage.
 34. A hair roller according to any of claim 31,wherein said deformable cage is integrally formed from a resilientmetallic sheet, foil or cylinder.
 35. A hair roller according to any ofclaim 31, wherein the resiliently deformable cage is formed of steel,aluminium or like resilient materials.
 36. A hair roller according toany of claim 31, wherein said deformable cage comprises a plurality oflongitudinally extending strips defining a plurality of longitudinallyextending channels located there-between, and wherein the totality ofsaid longitudinally extending strips forms a convexly curved bulgingsurface surrounding said rigid tube when subjected to an axialcompressive force applied at the axial ends of said cage.
 37. A hairroller according to claim 22, wherein each end clamping member comprisesa circular cap member and wherein at least one of said circular capmembers is rotatable relative to said hair curling portion and aboutsaid longitudinal axis.
 38. A hair roller according to claim 22, whereinprotrusions are distributed along the length of said hair curlingportion for hair retention by friction.